1. Field of the Invention
The present invention relates to a transfer device for use in image forming apparatuses of the electrophotographic type such as copiers, printers and the like.
2. Description of the Related Art
Full color copiers and printers of the electrophotographic type have become widely practical in recent years, and there has been increasing demand for improved image quality of various images such as text, graphic, and photographic images. There also has been demand improved image quality on a variety of types of paper in addition to color specialty paper, including thin sheet paper such as stationary stock, and thick sheet paper such as greeting card stock and the like.
In response to these demands, the transfer art for attaining excellent transfer to various kinds of paper and media of toner images in various states of adhesion, i.e., from monochrome toner images to three or four color toner images overlaid and even monochrome toner images include variable density levels ranging from solid to highlight, is an essential art in achieving high quality images and use of general-purpose paper in devices.
Transfer methods of full color image forming apparatuses using the electrophotographic method can be broadly divided into two types of transfer methods of the transfer drum method which sequentially transfers toner images adhered to the surface of a transfer drum to form a color image, and intermediate transfer methods which sequentially transfer toner images to an intermediate transfer body formed as an endless member made of an elastic material having electrical resistance. In recent years the intermediate transfer method has become widely used due to its advantages from the perspectives of using general-purpose paper, and compactness and low cost.